1. Field of the Invention
This invention relates to an air-massage device equipped with an inflatable air-mat. A human body can receive a massage treatment by lying on the mat, which is divided into three specific regions. A first region is designated for neck and shoulder areas of a person, a second region is designated for the waist, and a third region is designated for the lower extremities or legs. Within each of the three regions of the air-mat are installed a number of individual air-bags which can be inflated and deflated independently of each other.
2. Description of the Prior Art
Previously invented air-mat devices, such as Japanese Utility Model Publication No. 10994 (1991), are constructed so that a number of air-bags are installed in the body of the mat, and a human body lying on the mat can be massaged by independently inflating and deflating some of the air-bags by means of an intake/exhaust instrument installed within the air-mat device.
In addition, air-massage devices equipped with an air-mat divided into sections for the upper, middle and lower regions of the human body and provided with air-bags within each of these regions are known and currently used in the field.
These previous air-massage devices were designed to provide repeated massage therapy on a selected region of a human body by expanding and contracting the air-bags within a specified region. The air-bags are first expanded and contracted in a regular sequential order. Then, when the last air-bag at one end of the specified region has been expanded and contracted, the sequential order is reversed, so that the next to last air-bag will expand and contract, and then the second to last air-bag will expand and contract, etc. so that the expansion and contraction of each of the air-bags will proceed in an opposite direction.
Previous air-massage devices provide non-uniform massage treatments due to their method of expanding and contracting the air-bags within a specified region to be treated. Specifically, the air-bags of a prior art device are expanded and contracted in a regular order. When the last air-bag at the end of the specified region has been expanded and contracted, the expansion/contraction order is reversed so that the next to last air-bag will be the first air-bag to be expanded and contracted in the new reverse order. However, in such a method, the expansion/contraction frequency of the air-bags at the ends of the specified region will tend to be lower than the expansion/contraction frequency of the air-bags located inbetween the two end air-bags. For example, if a specified region of an air-mat contained three air-bags, A, B and C, the expansion and contraction of each of these air-bags would proceed in the following order: EQU A.fwdarw.B.fwdarw.C.fwdarw.B.fwdarw.A.fwdarw.B.fwdarw.C.fwdarw.B.fwdarw.A
Accordingly, during any one set period of time, the A air-bag is expanded/contracted three times, or has a frequency of three, while air-bag B has a frequency of four and air-bag C has a frequency of two. As one can observe, each air-bag within the specified region is expanded and contracted an unequal number of times compared to the other air-bags. As a result, the prior art massage device will provide an uneven or non-uniform massage.
Further, it was very troublesome to use the previously invented air-mat devices, as the body of the mat is covered with a material that is the same or similar to the material used to make the mat. Accordingly, the mat had to be used in conjunction with a separate cover, such as a blanket in the winter and a straw mat in the summer.
However, the use of a cover, such as a blanket or straw mat, upon the air-mat reduces the effectiveness of the massage treatment upon a human body lying on the mat as the cover impedes the massage effect produced by expansion and contraction of the air-bags within the mat.
Still further, in the previous air-bag devices, difficulties arise in determining the position of a human body lying on the body of the mat relative to the air-bags as the process of inflating and deflating the air-bags begins once the instrument has been turned on.